At a special Brian Ross investigation tonight US officials are in a race against time in Libya a country in chaos following the death of Qaddafi. They're scrambling to secure a massive stockpile of deadly shoulder fired missiles just one is powerful enough to take down a passenger plane. Brian first broke the story a month ago and tonight He brings us new evidence that the danger is still there. On the outskirts of the Libyan city of -- In an abandoned building a mile and a half from the airport large quantities of powerful explosives and deadly shoulder fired missiles were found unsecured. No sign of the US certainly Kate it -- This video taken on Sunday by an investigator for Human Rights Watch and provided to ABC news anybody -- -- -- miss out. All this a full month after US officials told ABC news they were moving quickly. To secure such unguarded weapons -- making progress. The hands of a terrorist it would take only one of the heat seeking missiles to bring down a commercial aircraft. Human Rights Watch investigator Peter -- says He believes hundreds of the missiles -- -- before He even got here. These facilities are still completely -- controlled. We didn't literally -- come here with a convoy of eighteen Wheeler tracks and I will delay whatever you vomit without even being noticed. There were an estimated 20000 of these missiles before the war. Same State Department official we talked to last month said today the US still cannot account for most of we believe. Thousands were -- right but it'll take some time to. Further identify a and refine that number but with a starting point of 20000 that still leaves a lot -- -- -- -- -- -- and that's why were were greatly concerned about this. As for the weapons discovered this site by human rights watch on Sunday part of the State Department says that they were moved to a new secure location just today. Just today and as of today there are still only about thirty US personal on the ground. Trying to keep those missiles the wrong hands George you have says -- is coming but right now thirty -- got to get through came from thanks very much.

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